medium
6.5
CWE
415
Advisory Published
Updated

CVE-2021-0271: Junos OS: EX2200-C Series, EX3200 Series, EX3300 Series, EX4200 Series, EX4500 Series, EX4550 Series, EX6210 Series, EX8208 Series, EX8216 Series: Receipt of a crafted ARP packet by an adjacent attacker will cause the sfid process to core.

First published: Wed Apr 14 2021(Updated: )

A Double Free vulnerability in the software forwarding interface daemon (sfid) process of Juniper Networks Junos OS allows an adjacently-connected attacker to cause a Denial of Service (DoS) by sending a crafted ARP packet to the device. Continued receipt and processing of the crafted ARP packets will create a sustained Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS on EX2200-C Series, EX3200 Series, EX3300 Series, EX4200 Series, EX4500 Series, EX4550 Series, EX6210 Series, EX8208 Series, EX8216 Series. 12.3 versions prior to 12.3R12-S17; 15.1 versions prior to 15.1R7-S8. This issue only affects the listed Marvell-chipset based EX Series devices. No other products or platforms are affected.

Credit: sirt@juniper.net

Affected SoftwareAffected VersionHow to fix
Juniper JUNOS=12.3
Juniper JUNOS=12.3-r1
Juniper JUNOS=12.3-r10
Juniper JUNOS=12.3-r10-s1
Juniper JUNOS=12.3-r10-s2
Juniper JUNOS=12.3-r11
Juniper JUNOS=12.3-r12
Juniper JUNOS=12.3-r12-s1
Juniper JUNOS=12.3-r12-s10
Juniper JUNOS=12.3-r12-s11
Juniper JUNOS=12.3-r12-s12
Juniper JUNOS=12.3-r12-s13
Juniper JUNOS=12.3-r12-s14
Juniper JUNOS=12.3-r12-s15
Juniper JUNOS=12.3-r12-s16
Juniper JUNOS=12.3-r12-s3
Juniper JUNOS=12.3-r12-s4
Juniper JUNOS=12.3-r12-s6
Juniper JUNOS=12.3-r12-s8
Juniper JUNOS=15.1
Juniper JUNOS=15.1-a1
Juniper JUNOS=15.1-f
Juniper JUNOS=15.1-f1
Juniper JUNOS=15.1-f2
Juniper JUNOS=15.1-f2-s1
Juniper JUNOS=15.1-f2-s2
Juniper JUNOS=15.1-f2-s3
Juniper JUNOS=15.1-f2-s4
Juniper JUNOS=15.1-f3
Juniper JUNOS=15.1-f4
Juniper JUNOS=15.1-f5
Juniper JUNOS=15.1-f5-s7
Juniper JUNOS=15.1-f6
Juniper JUNOS=15.1-f6-s1
Juniper JUNOS=15.1-f6-s10
Juniper JUNOS=15.1-f6-s12
Juniper JUNOS=15.1-f6-s2
Juniper JUNOS=15.1-f6-s3
Juniper JUNOS=15.1-f6-s4
Juniper JUNOS=15.1-f6-s5
Juniper JUNOS=15.1-f6-s6
Juniper JUNOS=15.1-f6-s7
Juniper JUNOS=15.1-f6-s8
Juniper JUNOS=15.1-f6-s9
Juniper JUNOS=15.1-f7
Juniper JUNOS=15.1-r
Juniper JUNOS=15.1-r1
Juniper JUNOS=15.1-r2
Juniper JUNOS=15.1-r3
Juniper JUNOS=15.1-r4
Juniper JUNOS=15.1-r4-s7
Juniper JUNOS=15.1-r4-s8
Juniper JUNOS=15.1-r4-s9
Juniper JUNOS=15.1-r5
Juniper JUNOS=15.1-r5-s1
Juniper JUNOS=15.1-r5-s3
Juniper JUNOS=15.1-r5-s5
Juniper JUNOS=15.1-r5-s6
Juniper JUNOS=15.1-r6
Juniper JUNOS=15.1-r6-s1
Juniper JUNOS=15.1-r6-s2
Juniper JUNOS=15.1-r6-s3
Juniper JUNOS=15.1-r6-s4
Juniper JUNOS=15.1-r6-s6
Juniper JUNOS=15.1-r7
Juniper JUNOS=15.1-r7-s1
Juniper JUNOS=15.1-r7-s2
Juniper JUNOS=15.1-r7-s3
Juniper JUNOS=15.1-r7-s4
Juniper JUNOS=15.1-r7-s5
Juniper JUNOS=15.1-r7-s6
Juniper JUNOS=15.1-r7-s7
Juniper Ex2200-c
Juniper Ex3200
Juniper Ex3300
Juniper Ex4200
Juniper Ex4500
Juniper Ex4550
Juniper Ex6210
Juniper Ex8208
Juniper Ex8216

Remedy

The following software releases have been updated to resolve this specific issue: Junos OS: 12.3R12-S17, 15.1R7-S8, and all subsequent releases.

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2021-0271?

    CVE-2021-0271 is classified with a high severity level, as it can lead to a Denial of Service (DoS).

  • How do I fix CVE-2021-0271?

    To fix CVE-2021-0271, you should upgrade the affected Junos software to a patched version provided by Juniper Networks.

  • Which versions of Junos OS are affected by CVE-2021-0271?

    CVE-2021-0271 affects several versions of Junos OS, including 12.3 and 15.1.

  • What impact does CVE-2021-0271 have on devices?

    CVE-2021-0271 allows an adjacent attacker to send a crafted ARP packet that can cause a Denial of Service (DoS) on affected devices.

  • Is there a workaround for CVE-2021-0271?

    Currently, the best protection against CVE-2021-0271 is to apply the security updates provided by Juniper Networks as there are no known workarounds.

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